By Alan Mozes
WEDNESDAY, March 14, 2018 (HealthDay News) -- A large study has confirmed what many public health experts have long believed: Colonoscopy saves lives.
The study looked at roughly 25,000 patients in the Veterans Affairs (VA) health system, where colonoscopy is widely used. The VA views it as the main screening test for patients aged 50 and older who have average odds for developing colon or rectal cancer.
Those who died were significantly less likely to have had a colonoscopy, the study found.
A comparison of screening histories over about two decades found that "colonoscopy was associated with a 61 percent reduction in colorectal cancer mortality," said study author Dr. Charles Kahi.
Kahi is gastroenterology section chief with the Roudebush VA Medical Center in Indianapolis.
The U.S. Centers for Disease Control and Prevention recommends everyone between the ages of 50 and 75 get screened for colon cancer. Those at high risk -- including those with a family history of the disease -- should be tested even earlier, the CDC advises.
Screening can take several forms, including stool tests; a lower colon exam called flexible sigmoidoscopy; and even a "virtual" colonoscopy that relies on X-rays to scan the entire colon.
But many public health advocates favor a full colon exam, or colonoscopy. For the test, a patient is typically sedated and a doctor inserts a flexible, lighted tube to examine the entire colon. If found, growths called polyps can be removed during the procedure.
Between 11.5 million and 14 million Americans have a colonoscopy each year, according to the study team.
The new study focused on patients aged 50 and older who were treated at VA facilities between 1997 and 2010.
The investigators found that a colonoscopy reduced the risk of death from right-sided colorectal cancer by 46 percent and left-sided cancer by 72 percent, equaling a combined drop of 61 percent.